Flexible, open-pored cleaning body

ABSTRACT

A flexible, open-pored cleaning body having at least one scouring surface (2) provided in at least one subregion with continuously formed, raised projecting ridges (3), wherein the ridges (3) have regions C,D of different heights in the direction of their extension.

FIELD OF THE INVENTION

The present invention relates to a flexible, open-pored cleaning bodyhaving at least one scrubbing surface which is provided in at least onesubregion with continuously formed, raised projecting ridges.

BACKGROUND INFORMATION

A cleaning body is described in German Utility Patent No. 7 612 130. Inthe patent, the ridges have an identical cross-section over their entirelength; they are arranged close to one another and separated from eachother by perpendicularly incised channels. They consist of the samematerial as the cleaning body and have a correspondingly highflexibility. When encountering adherent solid dirt laterally, a lateralbuckling is often observed, which makes little contribution to detachingthe dirt and subsequently removing it. Besides, the already detacheddirt components which penetrate into the interspaces between the ridgeshave a tendency to become fixed therein. They are hard to remove.

Another German Patent No. 27 30 266 describes cleaning bodies in which aplurality of isolated protuberances are arranged on a flat surface inclose proximity to one another. Such cleaning bodies do not make itpossible to wipe off a surface to be cleaned without leaving streaks.Further, the resistance of the protuberances to buckling decreases withincreasing height. Thus, to remove adhering dirt, it is necessary tomake the height of the protuberances very low. However, in so doing, animpairment of the dirt uptake capacity of the interspaces must bereckoned with.

SUMMARY OF THE INVENTION

An object of the present invention is to further develop a cleaning bodyin such a way that the mechanical removal of adhering dirt componentscan be achieved more satisfactorily than before.

According to the present invention, this task is accomplished with aflexible, open-pored cleaning body having at least one scrubbing surfacewhich is provided in at least one subregion with continuously formed,raised projecting ridges.

It is provided for the cleaning body according to the present inventionthat the ridges are formed in a continuous manner and have regions ofdifferent heights in the direction of their extension. Here, the presentinvention is based on the recognition that, as a rule, the thickness ofcontaminations covering a surface to be cleaned is largely uniform.Their removal with the use of the cleaning body according to theinvention is not intended to be done in a single step, but in such a waythat the ridges attack the dirt only at the most protuberant sites ofthe cleaning body, which makes it possible to exert at these sites highspecific contact pressures on the dirt through the ridges. In this waythe breakup and removal of the dirt at isolated places and/or during theforward movement of the cleaning body in the course of isolated scrapingis facilitated. It is advantageous that the raised sites of the ridgesare connected with each other via zones which protrude to a lesserextent, and therefore in a position to carry out a supplementarywindshield-wiper effect over their entire length. In this way, by movingthe scrubbing agent to and fro in closely adjacent streaks over asurface to be cleaned and substantially transversely or obliquely to thedirection of the ridges, complete removal of all dirt componentsadhering thereto is achieved within a short time. In addition, the areasof low height adjacent to the protuberances along the ridges providesaid protuberances with static support against lateral buckling. As aresult, the cleaning body is particularly suitable for use in thedomestic or industrial sector.

The ridges normally extend parallel to each other. They can be designedso that they have a straight-line, serpentine or zig-zag course. Adesign in which the adjacent ridges are arranged so as to fill gaps, atleast with regard to their protuberances, is also possible and canimprove the cleaning effect. In their course, the ridges cansuccessively change direction in an irregular manner, or beself-enclosing and have the form e.g. of a ring or ellipse.

With regard to its external shape, the cleaning body may be modified invarious ways. For example, it is possible to give it the form of acleaning cloth or a scrubbing sponge of parallelepiped shape.

Many possibilities exist also with regard to the materials used forfabricating the cleaning bodies. Apart from open-cell foams,fiber-containing materials such as fleeces or laminated materials, whichoptionally contain both foams and fibers, can also be used. In that casethe foams and fibers can have a blended structure or be imbedded in oneanother.

If fibers are used, it is merely necessary to ensure that the titer ofthe fibers not be too low. Advantageously, the titer should be in therange of coarse staple fibers, at about 0.2 to 40 dtex, preferablybetween 1 and 6.7 dtex. A supplementary or alternative use of metallicfibers can also be included in the considerations.

Used as foams are primarily soft, open-pored, polyurethane flexiblefoams having a density of from 15 to 200 kg/m³, preferably between 20and 50 kg/m³.

The use and preparation of the cleaning agent is particularly simplewhen the regions in which the ridges have a varying height regularlyfollow each other in a recurrent fashion.

According to an advantageous embodiment of the present invention, theregions of varying height are designed so that they blend into oneanother in a uniform manner. In this way the formation of streaks whenwiping smooth surfaces can be avoided in a particularly simple way.Ridges in which the regions of varying height follow each other in asinusoidal form are preferred.

To enable the cleaning body to be used in a way that is independent ofthe direction of the streaks during wiping processes, provision can bemade for the ridges to cross one another. When a regular pattern isused, this offers the possibility of producing the ridges without anywaste, in such a way that a thicker layer of the material forming thecleaning body is elastically deformed with the use of inflexible moldingmaterials of relief-like structure, and then split into two identicalcleaning bodies.

The mechanical resistance of the ridges to a lateral buckling movementcan be increased if they, viewed in the transverse direction, aredelimited by inclined surfaces. Viewed in the transverse position, thesesurfaces can have a curvature and optionally a sinusoidally blendingprofile.

The ridges are produced in one piece with the scrubbing agent made ofthe same material. Accordingly, in the case of unfavorable profiling,the mechanical strength under certain circumstances is very low. Toimprove this situation it has been found advantageous if the ratiobetween the distance of the midpoints of adjacent ridges and theirmaximum height is about 4 to 12, preferably from 6 to 9. Even with theuse of relatively easily deformable materials, adherence to this ratiomakes it possible to obtain an excellent wiping effect.

The scrubbing surface can be provided with a flexible coating whichimproves the abrasion resistance. Examples of coatings are described inU.S. Pat. No. 4,264,337. Within the framework of the present invention,a two-component polyurethane is preferentially used, which iscross-linked by subsequent heating and then hardened. In this way, thepenetration of the protuberances of the scrubbing surface into adherentdirt layers is further improved. Advantageously, such a coating isapplied to or pressed into the scrubbing surface in the liquid state,and then hardened. Particles of a scrubbing agent, e.g. particles of arubber granulate and/or an abrasive grain, may optionally be embeddedtherein.

For speedy performance of cleaning processes it is highly advantageousif, during the cleaning process, the cleaning body can be used as awater-storing means and if it is possible to displace the watercontained in the cleaning body e.g. by simple compression and thenre-release it toward the front side of the scrubbing surface, or if itcan be drawn away from it by suction. To meet this requirement, it hasproved useful for the coating to be permeable to liquids and, e.g., bepermeated by pores.

When the ridges are arranged obliquely to the longitudinal direction ofthe cleaning body, a wiper effect is obtained when it is used asspecified, which makes it possible to quickly remove liquids from largesurface areas.

Advantageously, the coating of the cleaning body is continuously appliedto the scrubbing surface during an elastic deformation with the aid of aroll mill, pressed into it to an at least partial extent, and thenhardened. In this way a particularly intimate bond results between thecoating and the cleaning body, which improves the durability of thecleaning body.

Found particularly advantageous has been a process for fabricating thecleaning body from open-pored foam, a process wherein a substantiallyflat foam mat is elastically deformed in a continuous manner betweenintermeshing projections of a pair of rolls, and, within the roll slit,is divided by a straight cut into two mat sections, which, on emergingfrom the roll slit, are delimited on the opposite sides by a corrugatedsurface, with the individual cleaning bodies obtained by being punchedout from the mat sections. This process operates without waste, and isthus advantageous from both the economical point of view and with regardto avoidance of waste materials.

In the aforementioned process a coating of liquid polymeric material,e.g. a solution of elastomeric polyurethane, is advantageously appliedto the corrugated surface of the mat sections, and is then hardened. Inthis way, the coating still in the liquid state can be pressed into themat section under continuous elastic deformation of said mat section.The application and pressing-in of the coating are most successful whenthe deformation is carried out with the aid of a roll mill, so that allsurface zones of said mat section are included. By operating in thisway, the coating surprisingly has a largely uniform layer density in allsubregions of the corrugated surface of the cleaning body, even thoughrolls having a cylindrical surface can be used. The components of thecoating situated in the region of protuberances and recesses of thescrubbing surface can thereby be mutually supported when transverseforces appear, a fact which improves the scrubbing effect and preventsdetachment of the coating when abrasive stress is exerted on theprotuberances. In general, the coating layer has a thickness of from 2to 5 mm, of which only about 1 mm extends beyond the surface of thefoamed body.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a view of the scrubbing surface of a typical cleaning bodyaccording to the present invention.

FIG. 2 shows a scrubbing surface wherein the highest points of theridges are marked with a star and the lowest points with a cross, and inwhich the position of the individual cutting planes according to FIGS. 3to 5 are indicated.

FIG. 3 shows the cleaning body according to FIG. 1 in sectionalrepresentation.

FIG. 4 shows the cleaning body according to FIG. 1 in another sectionalrepresentation.

FIG. 5 shows the cleaning body according to FIG. 1 in yet anothersectional representation.

FIG. 6 and FIG. 7 show a cleaning body in cross-sectionalrepresentation, and in a view of the scrubbing surface, whereinperpendicularly intersecting ridges are all arranged obliquely to thelongitudinal direction of the scrubbing body.

DETAILED DESCRIPTION OF THE INVENTION

In the drawing, the scrubbing surface of a cleaning body shown by way ofexample is represented in top view. In the area of the scrubbing surface2 (FIGS. 3 and 4), the cleaning body is comprised of a foam material 1of open-pored polyurethane foam having a bulk density of between 20 and50 kg/m³. On its top surface 4 (FIG. 3) continuous raised ridges 3 arearranged so as to form the scrubbing surface 2, said ridges forming twoperpendicularly intersecting ridge clusters. The ridge clusters form aone-piece component of the foam material 1 forming the cleaning body inthe region of the upper side. They are produced by a cutting process ina waste-free manner.

Within both ridge clusters, the distance between opposite midpoints ofadjacent ridges 3 is 30 mm, at a maximum height of 4 mm and a minimumheight of 2 mm, in each case in terms of that site of the profile wherethe latter attains its greatest distance from an imaginary prolongationof the top surface 4. The spatial position of the top surface isindicated in FIG. 3. The dimensioning can be varied as a function of thespecific use.

In the longitudinal direction the height of the ridges 3 variessinusoidally between sites of the greatest and smallest height C, D.Moreover in the transverse direction, the ridges 3 have the profile of abell-shaped curve. This is delimited at its base by the lines shown inFIG. 1. These lines are not recognizable on the product, because theridges 3 merge into the top surface 4 of the cleaning body by avoidingan abrupt change of direction and sharp edges. Furthermore, at thecrossing points, the limiting surfaces of the ridges merge into oneanother in a rounded-off fashion. Thus, the regions of varying heightsC, D of the ridges 3 again follow each other regularly in everydirection, with the individual ridges 3 nevertheless enclosingbowl-shaped recesses 5 in the manner of a waffle pattern. The base ofthe recesses 5 determines the position of the top surface above whichrise the ridges 3.

The recesses 5 are suitable for taking up, in a largely pressure-freemanner, relatively large amounts of dirt which are detached from asurface to be cleaned. Despite the exertion of considerable pressingforces, a rubbing-in action into the pore structure of the cleaning bodyis prevented, because these forces are absorbed predominantly by theridges 3 and, particularly, by those parts of the ridges 3 in which theyattain the greatest height C. Hence, after exceeding the lateral edgelimit of the body to be cleaned, the detached dirt components readilyfall out from the recesses 5, after which the original storage capacityis regained. In any case, a firm settling of such dirt components withinthe interior of the pore structure of the cleaning body is largelyprevented.

The scrubbing surface 2 is coated in its entirety with a layer ofcross-linked elastomeric polyurethane, which is applied in the course ofan impregnation process and is then hardened and bonded with thescrubbing surface 2 in an undetachable manner. In this way itsmechanical strength and, in particular, its abrasion resistance isconsiderably increased. In the transverse direction the coating ispermeated by pores. This results in a good water permeability in thedirection of the surface to be worked, which allows the amounts of waterstored in the open-pored structure of the cleaning body to be readilydisplaced toward the front side of the scrubbing surface 2 by pressureexerted on the cleaning body, or to draw them, together with thedetached dirt components, out of the scrubbing surface 2 during acleaning process when the pressure is released.

Worked into the coating is an abrasive granulate which may consist ofrubber particles and/or a scrubbing agent. In this way, even adheringdirt components can be eliminated from a surface to be cleaned withoutany difficulty.

The cleaning body shown in the drawing is provided with ridges 3 of thetype according to the invention only in the region of a scrubbingsurface 2. As a result the reverse side can be used to dry the surfacesthat are already cleaned. In the embodiment shown, this side is formedof a lining of viscous sponge 6, which is particularly well suited forthese purposes. By contrast, it is possible, if necessary, to providethis surface, or even additional surfaces of the cleaning body, withcorrespondingly or differently formed ridges 3. In such embodiments, thescrubbing surface 2 which is not being used momentarily is againcompletely freed from adhering dirt components through the millingmovements of the cleaning body with another scrubbing surface 2' whichoccur during the normal cleaning process, as well as through thepressure-free absorption and outflow of water through the pore structureof the unused scrubbing surface, and it is made suitable for a renewedapplication, without any special effort being required for this purpose.

FIGS. 6 and 7 show a cleaning body in the form of a cleaning cloth madeof foam which is produced homogeneously from a single foam block and isdelimited on its lower side by a flat surface. The top side is formed ofa scrubbing surface 2 which is structured analogously to theabove-described surface, but whose perpendicularly intersecting ridgeclusters are arranged obliquely to the longitudinal direction and at anangle of 45 degrees. Thus, the sites of greatest heights of the ridge 3,which follow one another in the longitudinal direction, are so disposedwith respect to each other so that they fill up gaps. In this way,despite relatively great opposite distances between the sites ofgreatest height D of the ridges 3, a nearly gapless attack on thesurface to be cleaned is attained in the operating direction which istransverse to the longitudinal direction.

If the cleaning body according to FIGS. 6 and 7 does not move over thesurface to be cleaned in a way that is exactly parallel to itslongitudinal direction, but is more or less rotated away from thatdirection, then an automatic improvement of the extent of mutualcovering of the strips cleaned through the sites of greatest height Dtakes place. On normal performance of a cleaning process, the thusoblique correlation of the longitudinal direction of the ridges 3 withthe direction of movement is almost always satisfied. Hence, within theframework of the present invention, an arrangement and design of theridges 3 in accordance with FIGS. 6 and 7 is preferred.

What is claimed is:
 1. A flexible open-pored cleaning body,comprising:at least one scouring surface; and a plurality ofcontinuously formed and raised projected ridges provided with the atleast one scouring surface in at least one subregion, the projectedridges disposed on a particular surface of the cleaning body, wherein,in a first region of the cleaning body, a particular ridge of theprojected ridges has a first length which extends from the particularsurface to a first peak of the particular ridge, wherein, in a secondregion of the cleaning body, the particular ridge has a second lengthwhich extends from the particular surface to a second peak of theparticular ridge, and wherein the first length is different from thesecond length.
 2. The cleaning body according to claim 1, wherein one ofthe first and second regions follows another one of the first and secondregions in a regularly recurring manner.
 3. The cleaning body accordingclaim 2, wherein the at least one scouring surface includes a flexiblecoating which improves a resistance to an abrasion.
 4. The cleaning bodyaccording to claim 3, wherein the flexible coating is formed in acontinuous manner.
 5. The cleaning body according to claim 3, whereinthe at least one subregion includes a plurality of subregions, andwherein the flexible coating has substantially same thickness in theplurality of subregions.
 6. The cleaning body according to claim 3,wherein the flexible coating is composed of an elastomeric polyurethanematerial.
 7. The cleaning body according to claim 3, wherein theflexible coating is applied to the at least one scouring surface in aliquid state, the flexible coating being subsequently hardened.
 8. Thecleaning body according claim 3, wherein particles of a scouring agentare embedded in the flexible coating.
 9. The cleaning body according toclaim 3, wherein the flexible coating is permeable to liquids.
 10. Thecleaning body according to claim 3, wherein the flexible coating isapplied to the at least one scouring surface by an elastic deformationof the cleaning body using a roll mill, the coating being subsequentlyhardened.
 11. The cleaning body according to claim 1, wherein the firstand second regions blend uniformly into one other.
 12. The cleaning bodyaccording to claim 1, wherein the first and second regions follow oneother in a sinusoidal manner.
 13. The cleaning body according to claim1, wherein when viewed in a transverse direction, the projected ridgesare delimited by inclined surfaces.
 14. The cleaning body according toclaim 13, wherein when viewed in a transverse direction, the at leastone souring surface has a curvature.
 15. The cleaning body according toclaim 14, wherein the curvature has a sinusoidal profile.
 16. Thecleaning body according to claim 1, wherein a first longitudinaldirection of the ridges is arranged obliquely at least with respect to asecond longitudinal direction of the cleaning body.
 17. The cleaningbody according to claim 1, wherein the first and second peaks are convexwith respect to the particular surface.
 18. A flexible open-poredcleaning body comprising:at least one scouring surface; and a pluralityof continuously formed and raised projected ridges provided with the atleast one scouring surface in at least one subregion, the projectedridges including a first region having a first height and a secondregion having a second height, the first and second regions extending ina particular direction in a direction of an extension of the projectedridges, the first height being different from the second height, whereinone of the projected ridges crosses another one of the projectedregions.
 19. A flexible open-pored cleaning body comprising:at least onescouring surface; and a plurality of continuously formed and raisedprojected ridges provided with the at least one scouring surface in atleast one subregion, the projected ridges including a first regionhaving a first height and a second region having a second height, thefirst and second regions extending in a particular direction in adirection of an extension of the projected ridges, the first heightbeing different from the second height, wherein the first height isgreater than the second height, and wherein a ratio of a distancebetween midpoints of adjacent ridges of the projected ridges to thefirst height is approximately 4 mm to 12 mm.
 20. A flexible open-poredcleaning body comprising:at least one scouring surface; and a pluralityof continuously formed and raised projected ridges provided with the atleast one scouring surface in at least one subregion, the projectedridges including a first region having a first height and a secondregion having a second height, the first and second regions extending ina particular direction in a direction of an extension of the projectedridges, the first height being different from the second height, whereinthe first height is greater than the second height, and wherein a ratioof distances between opposite midpoints of adjacent ridges of theprojected ridges and the first height is approximately 6 mm to 9 mm. 21.A flexible open-pored cleaning body, comprising:at least one scouringsurface; and a plurality of continuously formed and raised projectedridges provided with the at least one scouring surface in at least onesubregion, wherein, in a first region of the cleaning body, a particularridge of the projected ridges is separated from a first ridge of theprojected ridges via a first groove, wherein, in a second region of thecleaning body, a particular ridge of the projected ridges is separatedfrom a second ridge of the projected ridges via a second groove, whereina peak of the particular ridge extends at a first length from a firstbottom portion of the first groove and at a second length from a secondbottom portion of the second groove, and wherein the first length isdifferent from the second length.